The Southern Tree Breeding Association Inc. (STBA) is the national body which manages the Australian tree improvement programs for Radiata Pine (Pinus radiata) and Blue Gum (Eucalyptus globulus) and provides genetic evaluation services in forest trees. Forest growers must source the best genetics to suit their production environments if they are to generate financial returns while addressing environmental needs.
The STBA was formed in 1983 to develop improved genetics for plantation forestry. The business is based in Mount Gambier, but has expanded to service member companies in Western Australia, South Australia, Victoria, New South Wales , ACT, Tasmania and New Zealand . The STBA has consolidated genetic resources developed over more than sixty years by private companies, State and Federal Governments in order to breed better genetics more cost effectively.
Radiata Pine is the dominant softwood grown on more than 750,000 ha in Australia, targeting largely structural timber markets. Blue Gum plantations have expanded rapidly in the past two decades to more than 450,000 ha. This major hardwood species is grown on shorter rotations and targets chips for pulp and paper products.
The performance of trees in plantations is determined by the genetic makeup of the trees and the environmental conditions under which the trees are grown. Site selection (soil type and climate) and management practices (silvicultural regimes) will significantly impact on the growing environment and influence the productivity and quality of the forestry resource. Improved genetics can increase both profitability and quality, but without the need for additional silvicultural inputs, further increasing profits made from the sale and processing of improved forest product.
Productivity and profitability of trees grown in plantations will be maximised only by using the best genetics and silviculture in combination. Further, due to genotype by environment interaction, the best genotypes in one environment are not necessarily the best in another production region. For example, genotypes best suited to high rainfall areas may perform poorly relative to other genotypes under drier and more marginal conditions. As a consequence the STBA breeds genotypes specifically suited to the different growing environments and end product uses.
The STBA uses natural breeding methods to breed new trees by mating (cross-pollinating) superior females (flowers) with elite male (pollen) parents to produce higher performance progeny (seed) with improved growth rates and superior wood quality. Progeny of elite crosses are rigorously tested in many genetics trials which are planted across temperate Australia in order to identify elite trees with potential for improved productivity.
Individual tree data is collected on growth rates, branching characteristics, stem straightness and form, wood quality and fibre properties, and resistances to pests and diseases. This information is analysed on a national basis and used to select the best trees for use in each region.
STBA uses the leading edge TREEPLAN® genetic evaluation system for ranking trees on genetic merit. The TREEPLAN® system is a world first in that it can use all performance data and pedigree information available to produce robust genetic values for all production regions in Australia. The TREEPLAN® system of genetic evaluation has dramatically changed the way STBA tests and identifies elite material for Industry use, ensuring Members have the opportunity to capture gain without delay. The systematic approach enables STBA to undertake breeding activities every year and update TREEPLAN® breeding values regularly to assist in identifying the best material for use in industry deployment programs.
Traditionally tree breeders have focussed on improving characters associated with growth and tree form, and more recently wood quality. The objective of STBA is to breed trees which improve the financial returns to its member companies. In Blue Gum the target is to improve profits from growing trees for use in pulp and paper. For Radiata Pine, the objective is to improve the value of the harvested product for use in producing solid wood products.
Each tree in the breeding population for Radiata Pine has breeding values for a range of growth, form and wood quality traits including wood stiffness, which are combined in an economic index to reflect the commercial value of its genes. The performance of a tree is affected by the sum of all its genes and interactions. Placing too much emphasis on growth while ignoring wood quality can reduce the overall value of the forest resource.
The primary breeding objective for Blue Gum includes volume growth, wood basic density and pulp yield. Seed collected from genetically improved Blue Gum trees has the potential to return more than $2000 net present value (NPV) extra per hectare compared with unimproved native forest seed grown in the same plantations. New seed orchards being developed with this material by STBA Members and seedEnergy may deliver seed with an additional $1,500 NPV per hectare compared to seed currently being deployed. This extra profit can be captured for a small investment in breeding.
Access to elite genetic material (seed and clones) at commercially competitive prices is needed. The STBA provides scions for grafting by STBA member companies and seedEnergy Pty Ltd into seed orchards to produce commercial quantities of genetically improved seed. Quality genetics is also available to non-members of the STBA, but subject to payment of royalties when purchasing plants.
The STBA is also developing and testing Radiata Pine clones for commercial potential under Australian conditions. The STBA is a not for profit Association. It is more cost effective for forestry growers to be a member of the cooperative programs and share the operational cost of breeding with other companies.
The STBA has five member organisations that are internationally recognised as leading forestry and genetics research agencies: CRC for Forestry, ensis (a joint venture between CSIRO-FFP and Scion NZ), the University of Melbourne and the University of New England (AGBU). These partnerships in genetic research ensure the commercial breeding programs of STBA for Radiata Pine and Blue Gum are world class. Innovative research projects include the development of economic breeding objective functions for Pine and Blue Gum, the Juvenile Wood Initiative for Pine, and enhancements to the TREEPLAN® genetic evaluation system. Many research projects are also done in partnership with the Forest and Wood Products Research and Development Corporation.
With the introduction of TREEPLAN®, the STBA has been able to adopt progressive rolling front breeding and testing strategies for P. radiata and E. globulus . This means greater genetic gain is captured per unit time, but also more cost effectively for individual companies. TREEPLAN® allows industry to benchmark genetic material from different breeding programs, provided there are some related trees and data is made available for inclusion. TREEPLAN® is continually being enhanced to incorporate new innovation developed through research.
The STBA is currently establishing a National Genetic Resource Centre at Mount Gambier for breeding and conservation purposes. This will further consolidate the Pine and Blue Gum genetic resource, but also provide operational efficiencies in breeding operations.
STBA members (industry), Forest and Wood Products Research and Development Corporation and South Australian Government are funding this strategic initiative. The centre will service the Australian forestry sector, but also enhance relationships with the New Zealand industry.